Interactive electronic services, video-on-demand, and the "information superhighway" will provide access to thousands of movies, home shopping information, games, and other multimedia documents. A significant problem in using these systems is how to browse through the enormous choices to discover what is available, and to select items of interest. The conventional approaches to solving this problem are to use channel surfing, use advertisements on preview channels that act as entry points to other movies, and use hierarchical menus that users can navigate through with a remote control to make selections. These approaches do not scale up well to allow rapid browsing of the thousands of multimedia documents that will be available.
Interactive television (ITV) systems will be able to present the user with information displayed on the screen, much as PC user interfaces do today. These ITV systems will be limited, however, by the low resolution of NTSC screens, and the low resolution of pointing devices that are usable from across a room. When it comes to making rapid selections from a large number of choices, ITV systems are awkward and slow to use.